Question 7 Takes the Lot Size. The Town Keeps the Setback.

In Dallas, the Laura Court Addition subdivision was first drawn as 22 lots of 7,500 to 8,500 square feet. After Texas Senate Bill 15 took effect on Sept. 1, 2025, it was resubmitted as 59 lots of 3,000 to 4,000 square feet on the same land. AEI counted it among five Dallas developments, 746 homes in all, that cite the law in their approvals (AEI, Pinto and Gailes, July 29, 2026).

Massachusetts votes on its own lot-size measure on Nov. 3. Question 7 would bar towns from blocking a single-family home on a lot of at least 5,000 square feet with 50 feet of frontage and access to public sewer and water. If it passes, it takes effect about a month after the election and doesn't apply in Boston, which has its own zoning rules (WBUR, Oct. 7, 2026).

The Massachusetts text is built differently from the Texas law, and the difference decides yield. Question 7 would remove the lot-size floor on sewered land without setting a lot count, so a one-acre lot doesn't automatically become eight.

The count would come from the setback, bulk and height rules the text leaves with towns, and from the sewer and water capacity behind the pipe. If voters say yes, that's where the fight moves.

In-person early voting begins Saturday, Oct. 17, and runs through Oct. 30 (Secretary of the Commonwealth).

What the ballot text says, and what it leaves to towns

The measure would amend G.L. c. 40A §3, and its operative clause carries more conditions than the one-line summaries (Information for Voters 2026, Secretary of the Commonwealth, full text p. 41):

"No zoning ordinance or by-law shall prohibit, unreasonably restrict or require a special permit or other discretionary zoning approval for the use of land or structures for a single-family residence in a zoning district that allows residential uses; provided, that the single-family residence is fully contained within a lot measuring equal to or greater than five thousand square feet in area and with equal to or greater than fifty feet of frontage and which has access to public sewer service and public water service."

The next sentence hands the building envelope back to towns. The use "may be subject to reasonable regulations, including, but not limited to, regulations concerning dimensional setbacks and the bulk and height of structures" and to restrictions on short-term rentals.

"A zoning district that allows residential uses" reaches past single-family districts into any district where housing is allowed. "Fully contained within a lot" is the geometry hook: the house has to fit inside whatever envelope the setbacks leave.

"Unreasonably restrict" means towns may still restrict, and the text doesn't say where the line sits. "Access to public sewer service and public water service" isn't defined. The Act's title promises small lots "in areas with adequate infrastructure," but the operative clause never mentions capacity.

The Executive Office of Housing and Livable Communities "may issue guidelines or promulgate regulations to administer this paragraph," so EOHLC could end up defining "reasonable" in practice. At the March 16 initiative-petition hearing, EOHLC Undersecretary Chris Kluchman said municipalities "would not be forced to amend their zoning" but "must allow for land divisions as small as 5,000 square feet" (Banker & Tradesman/SHNS, Mar. 17, 2026).

Against current codes, that's a steep cut. More than half of Massachusetts land zoned for single-family homes requires lots of at least 40,000 square feet, eight times the Question 7 floor, and 24 percent requires at least 80,000 (National Zoning Atlas, Massachusetts 2026).

The statewide modeling is more modest. The measure would reach roughly 850,000 parcels, though most already permit single-family homes, and only about 200,000 would see their development status change (Boston.com, Sept. 22, 2026).

Tufts' Center for State Policy Analysis puts its central estimate at about 750 net new homes a year, and its researchers wrote that "impediments to construction are numerous and powerful" (Banker & Tradesman, June 9, 2026). The ones the report names are market and behavioral: high borrowing costs, a limited construction workforce and homeowners who never hear about the change. On a single parcel, the limits are geometric and hydraulic.

The math on ten sewered acres

This example is hypothetical. Every input is an assumption chosen to make the arithmetic visible, not drawn from any town's code or offered as typical.

Ten gross acres, 435,600 square feet. Sewered, on public water. A district with a 40,000 square foot minimum lot and 150 feet of frontage.

Today first. Assume 15 percent of gross area goes to the road plus the leftover slivers any large-lot layout produces. That leaves about 370,000 square feet, or about 9 lots at 40,000 each.

On a double-loaded road, 9 lots at 150 feet of frontage need about 9 × 150 / 2 = 675 feet of road, or 75 feet per lot. At a 50-foot right-of-way the road itself is only about 34,000 square feet, so roughly half of that 15 percent is remainder geometry.

Now the Question 7 layout, lot size only. Assume the road share rises to 20 percent, since smaller lots need more street. That leaves 348,480 square feet, or about 69 lots at 5,000 square feet.

Check the frontage. 69 lots × 50 feet / 2 is about 1,725 feet of double-loaded road, which at the same 50-foot right-of-way is about 86,000 square feet. That's roughly 20 percent of the parcel, so the assumption holds.

Road per lot falls from about 75 feet to about 25 feet, and sewer connections from the parcel go from 9 to about 69.

Each home now carries a third of the street it used to and a third of the main under it. Bob Dale, a New Hampshire developer, told Banker & Tradesman that building smaller would be "easier to get away with a lot less infrastructure costs" (Banker & Tradesman, Dec. 7, 2025).

The road still has to be permitted. Question 7 amends only c.40A §3 and leaves the Subdivision Control Law alone. Under G.L. c.41 §81L, a division is a subdivision unless every lot has the required frontage on a public way, an approved-plan way or a qualifying pre-existing way, so interior lots would need a new way.

In the hypothetical, that's 1,725 feet of new street on a definitive plan before the planning board. So the road math isn't what stops the 69.

Where the constraint moves: setbacks and bulk

Take one of the 69 lots: 50 feet wide, 100 feet deep. Assume the town keeps setbacks of 30 feet front, 30 feet rear and 15 feet on each side.

Subtract, and the buildable envelope is 20 feet wide by 40 feet deep, an 800 square foot footprint. Tight, but a narrow house fits.

Now raise the side setback to 20 feet on each side. The envelope narrows to 10 feet by 40 feet.

Nobody touched the lot-size rule. The lot still measures 5,000 square feet with 50 feet of frontage, but the envelope now holds a house 10 feet wide at most, and the house has to be "fully contained within a lot."

That's the "reasonable" question in one lot. Both numbers are dimensional setbacks, which the text lets towns regulate, and the ballot doesn't say whether the second one "unreasonably restricts" the use. EOHLC guidance, litigation or both would have to.

Bulk and height work the same way. A lot-coverage cap, floor-area ratio, height limit or building-width rule each shrinks the envelope and leaves the 5,000 square foot number alone. In this example, one row of the dimensional table moves yield more than the lot-size rule does.

What Texas cities did with the levers they kept

SB 15 applies in cities over 150,000 people in counties over 300,000, on unplatted single-family tracts of at least five acres. On those tracts, cities can't require lots larger than 3,000 square feet.

AEI reviewed 18 affected cities. It counted six as enabling small lots and classed four as "adding barriers": Arlington, Frisco, Grand Prairie and Killeen.

The requirements AEI lists sit in parts of the code the lot-size cap didn't reach. Arlington added alleys or access easements, a 60 square foot minimum front porch, 35 percent common open space, an amenity center and pool for subdivisions over 40 lots, and HOA responsibility for common areas.

Frisco added substantial front and rear setbacks, 15 percent usable open space and alley service. Grand Prairie required curvilinear streets and mandatory HOAs. Killeen required alley access for lots narrower than 40 feet and added impervious-surface standards.

Killeen staff, quoted by AEI, said the aim was to "mitigate the impact of SB 15 on the character and density of new residential development." AEI, whose authors support the law, says the barriers are expected to make homes "tens of thousands of dollars" more expensive.

Texas ran a similar test with SB 840, its by-right multifamily law, where outcomes have turned on each city's posture toward the statute (The Loophole War Over Senate Bill 840).

Here the two lot-size laws split: for lots of 4,000 square feet or less, SB 15 also limits the dimensional levers. It generally bars excessive setbacks, more than one required parking space, covered or off-site parking, and open-space or permeable-surface requirements above 30 percent. It also restricts home-size and articulation rules.

Even with those limits in the statute, AEI counted four cities adding requirements. Question 7 has no equivalent list and leaves every dimensional tool with towns, bounded mainly by the word "reasonable."

Where the constraint moves: the pipe and the plant

Pipe access is the first filter, and it's a hard one. Andrew Mikula, chair of the Yes on 7 campaign, called the water and sewer requirement "the biggest kind of built-in barrier to actually building these homes" (Massterlist, Oct. 6, 2026).

Capacity is the filter the text leaves out. In the hypothetical, 9 connections become about 69 on the same stub. Assuming similar flow per home, that's about 7.7 times the wastewater leaving the parcel, carried by whatever collector, pump station, interceptor and plant sit downstream.

At the March hearing, Ali DiMatteo, legislative and policy counsel for the Massachusetts Municipal Association (MMA), said "many, many municipalities with water and sewer are at or near capacity," per Banker & Tradesman, and pointed to North Shore towns already turning to the MWRA.

MMA Executive Director Adam Chapdelaine made the same point to WBUR: "Just because there's a water and sewer pipe there doesn't mean the overall system actually could handle that new load." NPR reported that some towns already see a need to expand sewer and water capacity, and Chapdelaine said "they are terrified that if this passes, that will completely upend those plans" (NPR via WGBH, Oct. 13, 2026).

For an engineer, the difference is a document. Pipe access is a map check. Capacity is a letter from the system that will take the flow, and on the 69-lot plan it has to cover about 7.7 times the 9-lot flow.

Houston as the long-run record

Houston has been running a version of this since 1998. That year the city cut its single-family minimum inside Loop 610 from 5,000 to 3,500 square feet, and to as little as 1,400 square feet under conditions.

Between 1999 and 2016, 25,269 residential parcels under 5,000 square feet were created, typically two or three townhouses replacing one detached house on a 5,000 square foot lot (Mercatus Center, Gray and McBirney, 2020). When Houston expanded the reform in 2013, it covered all the land in the city with wastewater collection infrastructure (CA YIMBY, summarizing Hamilton's 2023 Mercatus research).

Houston is a hard comparison. Mercatus calls it the only major American city without zoning, so its reform didn't sit inside a district's table of dimensional rules. A Massachusetts town would keep every row of that table if Question 7 passes.

What to check on a sewered parcel

If Question 7 passes, the 5,000 square foot headline is where diligence starts.

• Confirm with the sewer and water providers, not a GIS layer, that the parcel has public sewer and water access.
• Get a capacity letter covering full build-out flow rather than an availability map, and ask whether new connections would compete with a planned sewer or water expansion.
• Run lot yield on the town's current dimensional table at 50 feet of frontage, including setbacks, lot coverage, height and the envelope each lot leaves.
• Lay out road and frontage before counting lots. Question 7 amends only c.40A §3, so the Subdivision Control Law (G.L. c.41) still governs how new lots and ways are created, and lots without frontage on a qualifying way still need planning board approval of a plan.
• Pull recorded deed restrictions and HOA covenants on the parcel, because zoning reform doesn't remove them (private covenants survive zoning reform).
• Watch planning board and town meeting warrants for dimensional amendments and EOHLC for guidelines, and rerun yield when either lands.

Under Question 7, a sewered parcel's lot count would come out of its setback table and its capacity letter, and the land should be priced on those two documents.